The Probert Encyclopaedia of Science & Technology

BELL-CRANK

In machinery, a bell-crank is a rectangular lever by which the direction of motion is changed through an angle of 90 degrees, and by which its velocity-ratio and range may be altered at pleasure by making the arms of different lengths. It is much employed in. machinery, and is named from its being the form of crank employed in changing the direction of the bell-wires of house-bells.
Research Bell-Crank